Clip for radio frequency coils



Dec. 16, 1941. P, EHLERT CLIP FOR RADIO FREQUENCY COILS Filed oct. 15, 1938 xNvENToRs PAUL EHLERT BY r/ y ATTORNEY milled slot.

Patented Dec. 16, 1941 CLIP FOR RADIO FREQUENCY COlLS Paul Ehlertrerlin, Germany, assignor to Telefunken Gesellschaft fr Drahtlose Telegraphie m. b. H., Berlin, Germany, a corporation of Germany Application 4 Claims.

This invention relates to a new and novel clip for taking off current or 'voltages at any desired point of a tubular radio frequency coll.

A feature of this invention is the arrangement of a clip which is held against the tubular conductor of the coil by means of contact straps tensioned so as to provide an-elastic force.

Radio frequency coils used in large transmitter stations have of late been made frequently of lightmetal or other tubular ,parts instead of radio frequency litz` o rstranded wire. In order that satisfactory electric contact may bemade no matter at what point of such a radio frequency tubular coil, it'is necessary that the collector or tapping shoe should be pressed against a suiiiciently large area of the tubular piece. In the securing means heretofore in use a relatively wide contact band or strap laid around the .tubular coil `and hooked bilaterally on the fixed part of a tap shoe was tightenedV by screws .designed to pull the mobile part of the contact shoe away from the fixed part and press it against the tube. When this method is used in connection with tubular conductors, there is a risk of causing a permanent change in form or distortion of thel tubular radio frequency conductor by unduly iirm tightening of the screws, and this should be avoided byall means. When the screws, however, are less strongly tightened so that the above danger is avoided, safe and dependable contact is no longer insured even at temperature changes.

Hence, the problem is to establish at any prescribed places of a tubular radio frequency coilv as used in power transmitter stations safe contact even under conditions of heating in routine work, while avoiding permanent deformation of the tubular coil.'

According to the invention a split clip strap is used and the holderstrip which serves to make connection is rendered yieldable by means of a Moreover, screw. pressure is not brought to bear directly, but is transmitted rather by way of a spring or a spring packet upon the contact shoe bearing directly .upon the coil.

A more detailed description of the invention shall now be given by reference to the appended drawing. Fig. .1' of the drawing'shows the tube` contact one half in 'side elevation and half in section. Fig. 2 shows a section taken at right angles .to Fig.' l. Referring now in detail to the drawing, I denotes the .coil tube on which the contact is to be applied. 2 'is theholder strip or contact bearing member having a split 3 at its end and flared out to form a T-shaped contact portion serving to tap or take off current or october 15, 193s, serial No. 235,284 GermanyOctober 15, 1937 y each movable device, and means to apply pressure 4between each one of said contact straps vand D said movable devices to grip said conductor in potential with the contact shoe portion 4 A steel leaf type spring 5 transfers the pressure of the pressure or clamp screw 6 onto the contact shoe 4, on the one hand, and the mobile part 1, on the. other hand. Mobile part 1 is provided with two extension ears 1a. Bilaterally hooked on part 1 'is the contact strap or band 8 which is brought around the coil tube l. Band 8 has a slot 8a located on each end through which' ears la pass. 'I'he screws 9 serve solely for holding the assembly together without incidental transmission of any forces thereby. Holding screws 9 are secured to member 4 by being threaded into apertures 9a and are arranged to be freely slidable in the apertures 'Ib of members 5 'and` 1. By means `of the split 3'it is possible to adapt'the Contact shoes 4 to any particular form of the coil. The spring 5 insures perfect contact even if as a result of temperature changes or the like slight shifts or variations in size of the coil should spring member interposed between one of saidv contact shoe portions of said split holder and` a spring-like tension contact.

2. An adjustable contact clip for making contact to a conductor of radio frequency coil comprising a split holder strip forming two contact shoe portions, a pair of contact straps surrounding said shoe portions, Veach contact strap having' a slot located at each end'thereof,l a pair of movable ,devices each having engaging Ameans .for passing throughthe slots in each one of said contact straps, said contact straps arranged'to pass arounda portonofsaid conductor and the contact shoe portions of said split holder, a spring member interposed between one of said contact shoe portions of said split holder and each movable device, and meas including a. screw which is threaded in said movable devices to apply j pressure between said contact straps and said conductor.

a. An adjustable cgptsct cup for making com tact to a conductor of a radio frequency coil comprising a contact bearing element having a T-shaped end, a pair of U-shaped contact straps each one having retention means located at each end thereof. each one 'of said U-shaped straps located at an end of said T-shaped contact bearber interposed between each one of said movable devices and said contact bearing element, and

. means passing through said movable devices to apply pressure on said spring member to said conductor in a spring-like tension contact.

4. An adjustable contact clip for making contact to a conductor or a radio frequency coil com- 5 yprising a contact bearing element, a U-shaped contact strap having a slot located at each end thereof, a portion of said contact strap arranged to pass around a portion of said conductor, a movable device slidably supported to a portion lo' of said contact bearing element having engaging means adapted to pass through said slots in said ii-shapeci contact strap, 'a ilat spring member interposed between said movable device and said contact bearing element, and means passing 15' through said movablevdevice to apply pressure on said spring member to-grip said' conductor in a spring-like tension contact.

PAUL EHLERT. 

